var a = new Promise((resolve,reject)=>{
    setTimeout(() => {
        console.log("helloworld")
        resolve()
    }, 1000);
})
function b(){
    return new Promise((resolve,reject)=>{
        console.log("111")
        reject(123)
    })
}
b().then(()=>{
    console.log("html")
},(c)=>{
    console.log("css"+c)
})